Fatigue life sensitivity research for electric driving system in driving load cases and random vibration load cases

Abstract

In this paper, the fatigue characteristics of the electric drive system in driving load cases and random vibration load cases are analyzed numerically and experimentally. The fatigue life of the driving system under these two load cases is analyzed by using the time domain method and frequency domain method respectively. The results show that the damage of rotating parts (gear and bearing) mainly occurs in driving load cases, and the damage of gear and bearing in the driving load cases is 71.78% and 43.46% respectively. Fixed components (housing and suspension support) have certain damage in driving load cases and random vibration load cases, and the damage is greater in driving load cases. The damage of housing and suspension support in driving load cases is 10.6% and 0.167% respectively; the damage under random vibration load cases is 1.32 × 10⁻¹¹ and 3.12 × 10⁻¹¹ respectively. Based on the above conclusions, it is suggested that the driving load case tests for electric driving system are necessary, but it is not necessary to do random vibration tests only for electric driving system, or the number of random vibration tests can be reduced. This not only ensures the reliability of the components, but also helps to reduce the test cost.